vue 전역변수 설정방법

    publish(){
      const currentDate = new Date();
      console.log(currentDate);
      const getMonth = currentDate.toLocaleString('en-US', {month: 'short'});
      console.log(getMonth);
      const getDay = currentDate.getDate();
      let myPost = {
        name: "Kim Hyun",
        userImage: "https://picsum.photos/100?random=3",
        postImage: this.uploadImg,
        
        month: getMonth,  
        day: getDay,
        liked: false,
        content: this.writingText,
        filter: this.setlectedFilter,
      };
      this.infoData.unshift(myPost); 
      this.writingText = ""; 
      this.step = 0;
    }
라는 함수가 있는데
      const currentDate = new Date();
      console.log(currentDate);
      const getMonth = currentDate.toLocaleString('en-US', {month: 'short'});
      console.log(getMonth);
      const getDay = currentDate.getDate();
변수들을 따로 전역으로 옮기려면 어디에두어야하나요